2027 ICD-10-CM Diagnosis Code M79.631Pain in right forearm
ICD-10-CM Codes›M00–M99›M70-M79›M79
- Billable — Valid for Submission
- Not Chronic
M79.631 is a billable ICD-10-CM diagnosis code for pain in right forearm. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 555 through 556. Coders also document this condition as pain in forearm. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Musculoskeletal pain, not low back pain.
This medical diagnosis code is frequently used in Family Practice, Internal Medicine, and Pediatrics medical specialties to designate conditions such pain in limb.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Pain in forearm
- Pain of bilateral forearms
- Pain of left forearm
- Pain of right forearm
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to M79.631: its own notes plus those printed at M79.6, M79, and Chapter 13. A note printed at a category, block or chapter applies to every code under it.
Excludes1
Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
- arthropathic psoriasis (L40.5-)
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- compartment syndrome (traumatic) (T79.A-)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Notes
General instructions on how these codes are used.
- Use an external cause code following the code for the musculoskeletal condition, if applicable, to identify the cause of the musculoskeletal condition
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name M79.631, its category, or a range that includes it.
Excludes1 1
These codes carry an Excludes1 note naming M79.631: they are not reported together with it, unless the two conditions are unrelated.
Excludes2 3
These codes carry an Excludes2 note naming M79.631: its condition is not part of those codes, and both may be reported when the patient has both.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Arm Injuries and Disorders
Of the 206 bones in your body, three of them are in your arm: the humerus, radius, and ulna. Your arms are also made up of muscles, joints, tendons, and other connective tissue. Injuries to any of these parts of the arm can occur during sports, a fall, or an accident.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert M79.631 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About M79.631Overview
What is the ICD-10 code for pain in right forearm?
The ICD-10-CM code for pain in right forearm is M79.631 (sometimes written as M79631). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is M79.631 (Pain in forearm) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report pain in right forearm on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does M79.631 group to?
When pain in right forearm is the principal diagnosis on an inpatient stay, it groups to MS-DRG 555, 556, with relative weights from 0.8210 to 1.2908 depending on complications. Higher weights mean higher Medicare reimbursement.
Can M79.631 be reported with F45.8?
Not as a rule. The Excludes1 note at M79, which applies to M79.631, lists "psychogenic rheumatism (F45.8)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).
What is the ICD-9 equivalent of M79.631?
Under the General Equivalence Mappings, pain in right forearm converts to ICD-9-CM 729.5 (pain in limb). The mapping is approximate, so confirm the match fits the documentation.
